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@article{MZM_1999_65_5_a14, author = {R. I. Grigorchuk}, title = {Ergodic theorems for the actions of a~free group and a~free semigroup}, journal = {Matemati\v{c}eskie zametki}, pages = {779--783}, publisher = {mathdoc}, volume = {65}, number = {5}, year = {1999}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1999_65_5_a14/} }
R. I. Grigorchuk. Ergodic theorems for the actions of a~free group and a~free semigroup. Matematičeskie zametki, Tome 65 (1999) no. 5, pp. 779-783. http://geodesic.mathdoc.fr/item/MZM_1999_65_5_a14/